Comparing Sustained Release and Extended Release to Other Types
Sustained release and extended release are relative terms. Before we discuss extended release vs. sustained release, it would be helpful to understand the other types of medication they're compared to.
Immediate Release (IR)
Immediate-release tablets are exactly what they sound like. The medication is released soon after the pills are ingested. The drug works quickly over a short period. When IR tablets are prescribed, patients are often required to take several doses daily to ensure a constant supply of medication.
Controlled Release (CR)
Controlled-release tablets are a type of medication designed to gradually release a drug into a patient's system over a certain period. This differs from conventional immediate-release tablets that release their active ingredients as soon as they are ingested.
Controlled-release systems can maintain a constant drug concentration over a prolonged period, reduce the frequency of dosing, minimize side effects and enhance the efficacy of the medication. They can be especially useful in place of drugs that need to be taken several times a day or for conditions that require a constant level of medicine in the bloodstream.
Ambien CR is one example of a controlled-release drug. While Ambien IR can wear off before the night ends, Ambien CR delivers a constant rate of medication, ensuring a good night's sleep from start to finish.
The design of CR tablets can vary greatly, with some utilizing different drug coatings, materials or technologies to control the rate, location or timing of drug release.
Delayed Release (DR)
Delayed-release drugs are designed to release the active ingredient later than immediately after administration. This delay could be based on a certain period after ingestion or until the drug reaches a specific part of the gastrointestinal tract. The design of delayed-release tablets allows the medication to bypass certain areas of the digestive system, which can be beneficial for drugs that are destroyed by stomach acids or for medicines that can irritate the stomach lining.
One example of a DR drug is sulfasalazine DR, used to treat ulcerative colitis.
While delayed-release formulations are designed to control when the drug is released, they don't necessarily control the rate at which it is released once the delay period has ended. In other words, once the drug is released, it may spread rapidly or all at once, differentiating these formulations from sustained-release and extended-release tablets.
Pulse Release
Pulse-release drugs, also known as pulsatile-release drugs, are a type of medication designed to release the active ingredients in a predetermined pattern over a specific period. This can involve one or more "pulses" of drug release to mimic the body's natural rhythms, respond to a particular physiological need or optimize the drug's therapeutic effect and minimize side effects.
The release mechanism can be designed to respond to a variety of factors. For example, it can be programmed based on time (time-controlled release), or it can react to specific physiological signals such as pH changes in different parts of the gastrointestinal tract (pH-dependent release) or the presence of certain enzymes or substances in the body (chemically-induced release).
This type of drug delivery system can be particularly beneficial for conditions that follow a circadian rhythm (like rheumatoid arthritis, where symptoms are often worse in the morning) or for situations that require a burst of medication at specific times (like peptic ulcer disease, which might require a release of drug in response to a rise in gastric acidity).
One example of a pulse-release drug is Prednisone chronotherapy for rheumatoid arthritis. The prednisone is formulated to release the drug in the early morning hours when symptoms are most severe.
Sustained-Release and Extended-Release Tablets
While some companies differentiate between the two types, at UPM Pharmaceuticals, there is no difference between sustained release and extended release; we use the two terms interchangeably.
The main goal of extended-release tablets is to maintain an appropriate concentration of the drug in the body, thereby providing a prolonged therapeutic effect. This is achieved by using different pharmaceutical manufacturing technologies that control the rate at which the drug is released from the tablet. These can include special coatings, matrix systems or encapsulation techniques.
By reducing the number of doses needed, sustained-release tablets can improve patient compliance with their medication regimen. They can also help minimize side effects that can occur when drug levels in the body peak and trough, as can happen with immediate-release formulations.
Examples of extended-release tablets include certain formulations of common medications like metoprolol (a beta-blocker used for treating high blood pressure), venlafaxine (an antidepressant) and theophylline (used for respiratory diseases like asthma).
FAQs
Sustained release's definition is more akin to a "controlled release" rather than "sustained". Extended-release dosage consists of either sustained-release (SR) or controlled-release (CR) dosage. SR maintains drug release over a sustained period but not at a constant rate.
How do extended-release pills work? ›
Extended-release tablets are medications designed to release an active ingredient over a specific duration gradually. Instead of being immediately released and absorbed once ingested, the drug in these tablets is distributed steadily in the body, ensuring a prolonged therapeutic effect.
How does sustained release medication work? ›
Sustained release allows delivery of a specific drug at a programmed rate that leads to drug delivery for a prolonged period of time (Moghimi et al., 2001). This approach of drug release is especially useful for drugs that are metabolized too fast and are eliminated from the body shortly after administration.
What is the difference between CR and SR tablets? ›
The key differences between controlled release and sustained release include: Sustained release is a slow release of medication over a period of time, whereas control release releases medication over time in correlation with concentration.
Is SR and ER the same thing? ›
The correct responses for the first and second questions were as follows: CR = controlled release (long-acting), SR = sustained release (long-acting), ER = extended release (long-acting), and IR = immediate release (short-acting).
What are the disadvantages of sustained-release? ›
Disadvantages of using sustained release tablets include:
-They may not work as quickly as other types of tablets if the body needs a quick burst of medication to treat an acute condition. -They may be more expensive than other types of tablets because they contain higher doses of medication.
How long does it take for an extended-release pill to work? ›
When the medication is swallowed, it begins working to relieve pain in about 2 to 4 hours, although it reaches its peak effect in 15 to 30 hours. It will continue to work for a few days. This type of medication is designed to produce a long-acting, steady amount of pain relief.
How long does it take for an extended-release pill to digest? ›
Extended-release medications are slowly released into the body over a period of 12 to 24 hours. These extended-release medications where the shell has been left behind are sometimes referred to as "ghost pills" or "ghost tablets," meaning there is only the outer shell of a pill with no active ingredients remaining.
What does the enteric coating on a medication tablet do? ›
Enteric coating is a common procedure in the development of oral pharmaceutical dosage forms. The main advantage of enteric coating is that it protects the drug from acidic pH and enzymatic degradation in the stomach while protecting it from the undesirable effects of some drugs.
What is meant by sustained-release? ›
adjective. sus·tained-re·lease səs-ˌtānd-ri-ˌlēs. : designed to slowly release a drug in the body over an extended period of time especially to sustain therapeutic levels. sustained-release capsules. a sustained-release drug delivery system.
When crushing disrupts a drug's sustained-release properties, the active ingredient is no longer released and absorbed gradually, resulting in overdose. When a gastro-resistant layer is destroyed by crushing, underdosing is likely.
Can you break sustained-release tablets? ›
Most sustained, controlled, or time-released medications aren't meant for splitting because they are designed to release medication throughout a specific period of time. By cutting a time-released medication, you run the risk of having too much or too little in your body at once.
Are CR and Er the same thing? ›
Most managed care pharmacists have quipped at one time or another that SR (sustained release) at the end of a drug name stands for sustained revenue, ER (extended release) really means extended revenue, and CR (controlled release) really means continued revenue.
Is metformin ER and SR the same? ›
Metformin IR and metformin ER work the same way to treat prediabetes and Type 2 diabetes — they just differ in how quickly they're released in the body. They have similar benefits and risks, but metformin ER tends to cause fewer side effects.
Do extended-release pills work better? ›
Though they typically take longer to kick in compared to their IR counterparts, XR medications maintain a more consistent level of the medication in your body. This could mean better treatment outcomes for longer periods of time while also lowering the chances of side effects.
Why use sustained-release? ›
Benefits of Sustained Release Tablets
Provides the ability to maintain a constant level of medication within the body. Eliminates the likelihood of burst drug release. Reduces the number of doses which lowers expenses and improves patient compliance, especially for chronic diseases. Decreases side effects.
What are the advantages of sustained-release? ›
Reduced side effects: Sustained release tablets may be less likely to cause side effects compared to other forms of medication because they release their active ingredients gradually over time. This can help to reduce the severity of side effects and improve overall tolerance of the medication.
What is the meaning of sustain release? ›
adjective. sus·tained-re·lease səs-ˌtānd-ri-ˌlēs. : designed to slowly release a drug in the body over an extended period of time especially to sustain therapeutic levels. sustained-release capsules. a sustained-release drug delivery system.
